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   /*
    * Copyright 2017 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   https://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package io.netty.buffer;
  
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.Measurement;
  import org.openjdk.jmh.annotations.Mode;
  import org.openjdk.jmh.annotations.Param;
  import org.openjdk.jmh.annotations.Threads;
  import org.openjdk.jmh.annotations.Warmup;
  
  @BenchmarkMode(Mode.Throughput)
  @Threads(16)
  @Warmup(iterations = 5)
  @Measurement(iterations = 10)
  public class ByteBufNoCleanerChangeCapacityBenchmark extends AbstractByteBufNoCleanerBenchmark {
      private static final int MAX_DIRECT_MEMORY_PER_THREAD = 1024 * 1024; // 1 mb per thread.
  
      @Param("1024")
      public int initialCapacity;
  
      @Benchmark
      public boolean capacityChange() {
          ByteBuf buffer = bufferType.newBuffer(initialCapacity);
          // Change capacity until we would exceed the 1mb per thread limit
          for (int newCapacity = initialCapacity << 1; newCapacity <= MAX_DIRECT_MEMORY_PER_THREAD;
               newCapacity += initialCapacity) {
              buffer.capacity(newCapacity);
          }
          return buffer.release();
      }
  }